The Ancient Greek words for sympathy and empathy (which then found their way into Latin) can provide insight into to their meaning today.

They have a common root, the "pathy" part. It derives from the Greek word "pathos" (πάθος), which means "pain, suffering, passion".Prefixed to the root are conjunctions: “sym” meaning "with" (from "sun", σύν) and "em" meaning "in" (from "en", ἐν). This adds up to:

Sympathy is "pain with": to feel the pain with someone.

Empathy is "pain in": to feel the pain in someone.

Sympathy, in its positive understanding, means we identify with the person's pain because we’ve experienced the same or a similar situation.

Empathy takes it up a notch: we feel the person’s pain, even though we do not personally relate to their situation.In other words:

Empathy is putting yourself in someone's shoes and feeling: “I don’t know what it’s like, mine feel nothing like that. But I relate to how they make you feel.”

Empathy is priceless when we're incapable of identifying with the person, for instance, when people do things we could never picture ourselves doing.

Empathy allows us to connect with them by identifying with their feelings and emotions, even though we consider their actions and behavior unacceptable.To give an extreme example, we might identify with someone’s overwhelming feelings of fear, intimidation and threat to their safety, but still feel incapable of committing the homicide they committed.Sympathy is easy. For life's challenges, like John, I prefer empathy.